Federal prosecutors in Arizona have submitted supplemental briefing in the case against Donald Day Jr., a self-described sovereign citizen accused of making online threats. The filing aims to clarify Day’s alleged knowledge of the Australian Wiembilla shooting—an ambush that left two police officers and a civilian dead in December 2022, perpetrated by the radicalized Train family.
At issue is whether Day had tactical knowledge of the Trains’ remote Australian compound and whether his threatening online remarks were influenced by that connection. Prosecutors highlighted several points:
YouTube Conversations: Day interacted with Gareth and Stacy Train on YouTube. Gareth invited Day and his wife to “100 acres” of property in Australia, while Stacy hinted at ongoing police surveillance, calling it “state sponsored murder.”
Comments Supporting Violence: After the Trains posted a video mocking police, Day commented, “we teach those fuckers how we are to be treated,” thanking them and calling the world better for their presence.
Post-Arrest Statements: Day allegedly told investigators that the Trains had their property rigged with basic surveillance like mirrors and cameras, and that he had offered them a house and land in the U.S. to escape persecution.
Google Searches After the Shooting: Just days after the Trains’ deadly ambush, Day’s Chrome history showed extensive searches on the incident using DuckDuckGo and other platforms.
The government argues this evidence shows Day was well aware of the Trains’ setup and ideological mindset, and that this context supports the intent behind his own threatening online behavior—the subject of Count One in the indictment.
The case continues in the U.S. District Court for the District of Arizona.